Özet:
In this study, we analyse the behaviour of the coinfection of the HIV-TB model using a piecewise operator in the classical-Caputo sense. For the aforementioned disease model, we present the existence as well as the uniqueness of a solution having a piecewise derivative. We also study the different versions of stability using Ulam–Hyers stability in nonlinear analysis. We use the piecewise Newton polynomial technique to obtain an approximation of the solution to the proposed problem. The simulations for the suggested coinfection model are presented. The simulations are carried out for the disease-free as well as endemic equilibrium. Additionally, the comparison between the simulated and real data is presented, where we obtain the best-fitted dynamics of the infected class with TB.